Hull construction



NOV. 10, 1931. H, z E 1,831,697

HULL CONSTRUCTION Filed June 3, 1929 1;: 76 INVENTOR JZZzrry Ziegler ATTORNEY Patented Nov.1 0, 193l UNITED STATES PATENT OFFICE Application ma Inc a, 1920. mm Io. seam.

This invention relates to a hull construction for boats, seaplanes and pontoons for marine craft. I y The principal object of the invention is to 8 provide a hull of the indicated character, embodying novel features of construct1on, whereby to decrease the wetted surface, or the wetted perimeter at any section thereof; to decrease the adhesion of hull and water; to obtain a material increase in speed by reducing skin resistance; to obtain a given s eed with less ower; to double the bottom 0 the hull and thus increase the safet fac'tor therew of; to increase the strength wit out material- 1 increasing the weight of the hull; and to decrease the take-ofl run in case of seaplanes and allow them to car increased loads.

The invention will be e'st'understood from a consideration of the following specification,

. limited to any strict conformity with the showing in the drawings, but that the character of the material used and the details of the construction may be changed ormodified within the spirit of the invention as expressed in the appended claims.

In the drawings:

Figure 1 is an outboard profile of a. hull constructed in accordance with the invention.

Fig. 2 is a bow view.

. Fig. 3 is an enlarged transverse sectionalview taken on the line 3-3 of Fig. 1.

Fig. 4 is a central longitudinal section of the bow.

Referring now more particularly to the drawings, it will be apparent that for the sake of simplicity the hull of the present invention is one which is designed to be constructed entirely of metal, which will be of sufficient thickness so as to eliminate the neoessity of ribs or other reinforcing members. It is to be understood that the features of the invention may be incorporated in a hull whether for a boat or seaplane, or pontoon for marine craft. It is further to be understood 0 that the hull may be constructed of wood,

metal alloys, or combination of these materials as well as metal.

The hull, which as stated is made of metal, includes an inner bottom 10 and an outer bottom 11 joined to the sides 12. An air Egssa e or opening 13 is rovided in the w or the pur of 'tting air between the bottoms 10 and 11 in the forward movement of the hull. The outer bottom 11 is constructed to present overlappin portions which define a series of slots, sits or narrow openings 14 occurring transversely with respect to the longitudinal axis of the hull. The bottoms 10 and 11 are arcuate in cross section in the present instance. The inner bottom 10 is arched or curved in an upward direction and joins the lower edges o the sides 12. The outer bottom 11 is constructed of overlapping portions, as stated, and each of these portions is arched or curved in an upward direction from the keel of the hull at each side thereof to the junctures of the bottom 10 with the sides 12. This construction increases the safety factor and also increases the strength of the hull without materially increasing its weight. The opening or passa e 13 may be at the front, sides, top, or may ranch to any combination of these plams and lead between the bottoms 10 and 11. The openin or passage may be of any size and of sue dimensions as to meet sufficient on-coming air, so as to create a positive pressure between the two bottoms. If desired a fan or pro Her may be operatively positioned in t2: opening to accom lish tnis result.

e slots 14 serve the purpose of discharging the water which has accumulated between the two bottoms,'when the hull was at rest, and also for the purpose of discharging the air entering the opemng or passage 13, when the hull has attained sufiicient acceleration, and water between said bottoms has been discharged. v

The space between the bottoms will be cleared of water by the acceleration of the hull, which will tend to shift or crowd the water to the rear, thus forcing it out through the slots 14. The air enterin the opening or passage 13 will be forced in between the two bottoms, and thus create a positive pressure, and aid in forcing the water out through the slots. The water met by the outer bottom of the hull in the forward movement thereof will cause a suction action at the slots 14 and thus aid to draw the water out from between the bottom. When the water that was between the bottoms is out, the air that is entering the opening or passage 13 will be forced out and spread over the outer bottom, and thus decrease the wetted surface. Incidental to decreasing the wetted surface there will be a decrease of adhesion of hull and water, thereby enablin a material increase in speed by reducing t e skin resistance, or the obtainment of a power. It will also e apparent that the hull will have a double bottom construction of practical form which will increase the safety factor and also increase the strength thereof without materially increasing the weight of the hull.

I claim:

1. A marine craft hull having an inner and outer bottom defining a space closed at the sides extending longitudinally of the hull together with a series of rearwardly directed slots or o ni in communication with said space, an provision to admit air at a forward point above the water line into said space by the forward movement of said hull to be discharged through said slots or openings, for the purpose specified.

2. A marine craft hull having a passage for entrapping air at a point above the waterline and for directing the air rearward- 1y of the bottom of the hull in the forward movement of the hull, and an outer bottom having overlapping portions defining rearwardly directed openings through which the entrapped air may flow.

3. A marine craft fiotable hollow body having sides, and an inner and outer bottom, said outer bottom consisting of overlapping sections joined to said sides of the body in spaced relation with respect to each other and said inner bottom, and said body having a passage for entrap ing air at a point above the waterline of said body and for directing the air rearwardly between said sections to decrease the adhesion of said body and watcr in the movement of the body in water.

4. A marine craft hull having an inner and outer bottom defining a space extending longitudinally of the hull, together with a series of rearwardl directed slots or openings in the outer ottom in communication with said space, and a passa e extending rearwardly and downwardly o the hull for admitting air at the bow above the waterline and directing it into said space b the forward movement of the hull to be ischarged therefrom through said slots or openings, for the purposes specified.

5. A marine craft flotable body having an given speed with ham other.

HARRY ZIEGLER. 

